The present invention pertains to the mounting of an assembly composed of semiconductors (such as thyristors, transistors or diodes) and heat sinks stacked alternately upon one another between two plates which are to be fastened by means of threaded rods, with the aforementioned heat sinks serving not only to ensure removal of heat, but to provide connections with the surfaces of the aforementioned semiconductors.
In more specific terms, the present invention pertains to a means of clamping and securely positioning an assembly composed of electrical semiconductors and heat sinks of the previously indicated type, which is simple to use, while also reliably ensuring the level of clamping force applied to the assembly.
The present invention is particularly applicable for mounting semiconductors for traction equipment intended for shipping, wherein minimization of overall dimensions is of prime importance.
French Patent Application No. 82 11371, which was submitted on June 29, 1982, discloses one technique to accomplish high-pressure locking of a column of alternately stacked semiconductors and heat sinks between two plates fastened by means of threaded rods. This technique involves the use of a screw which extends axially through one of said plates, so as to apply the required clamping pressure to the stacked elements from a point located along the axis of the column.
In this particular instance, tightening torque is applied by means of a dynamometric wrench, in order to transmit clamping pressure with maximum precision.
It is also possible to accomplish the same result with the previously cited assembly by applying clamping pressure axially to the column through the threaded rods which fasten the plates together, by employing a clamping press of the type described in French Pat. No. 2,415,514. These methods are effective and satisfactory, but since it is necessary to apply clamping pressure directly to the aforementioned assembly with the use of either a press or a dynamo-metric wrench, considerable precision is required.